The present invention relates to an image forming apparatus such as a printer and a digital copying machine.
Image forming apparatuses, such as digital copying machines, generally have a printer function, whereby documents created by external equipment, such as a personal computer, can be printed, and a copier function, whereby original documents can be copied. Some image forming apparatuses have a toner saving mode in which, to save toner, printing is carried out with the amount of toner used controlled more than usual.
Where there is a need to print a document in great numbers, the document may be proof printed in order to confirm the arrangement of printed document images. If the arrangement of a page image of the document proof printed by the image forming apparatus is correct, the user prints the required number of copies of the document. The main object of proof printing is to confirm the arrangement of printed document images. Thus, the toner consumption can be reduced by choosing the toner saving mode at the time of proof printing by way of example.
Conventionally, methods of printing with toner consumption reduced in an image forming apparatus include methods disclosed in Jpn. Pat. Appln. KOKAI Publication No. 9-39298 (image recording apparatus and image recording method) and in Jpn. Pat. Appln. Publication No. 8-123257 (electrophotographic apparatus).
In Jpn. Pat. Appln. Publication No. 9-39298, if, when the recording material saving record mode is on, pixels are decided to be included in an area where toner is to be heavily coated, image information for these pixels is changed to low-density recording information and then low-density recording is made on the basis of the changed image information.
In Jpn. Pat. Appln. Publication No. 8-123257, in the toner saving mode the data width per dot is reduced through control of the controller, thereby reducing the toner consumption. In this publication as well, only when the user specifies the toner saving mode, the toner consumption is reduced through control of the controller.
Thus, with the conventional image forming apparatus having the toner saving mode in which printing is made with toner consumption controlled, the toner consumption will not be reduced unless the said mode is turned on. That is, the user is required to consider what purpose document images to be printed are used for and then turn the toner saving mode on or off for each document. Such operation is troublesome.